2 * Copyright © 2014-2017 Intel Corporation
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
24 #include <linux/debugfs.h>
25 #include <linux/relay.h>
29 static void guc_log_capture_logs(struct intel_guc *guc);
32 * DOC: GuC firmware log
34 * Firmware log is enabled by setting i915.guc_log_level to non-negative level.
35 * Log data is printed out via reading debugfs i915_guc_log_dump. Reading from
36 * i915_guc_load_status will print out firmware loading status and scratch
41 static int guc_log_flush_complete(struct intel_guc *guc)
44 INTEL_GUC_ACTION_LOG_BUFFER_FILE_FLUSH_COMPLETE
47 return intel_guc_send(guc, action, ARRAY_SIZE(action));
50 static int guc_log_flush(struct intel_guc *guc)
53 INTEL_GUC_ACTION_FORCE_LOG_BUFFER_FLUSH,
57 return intel_guc_send(guc, action, ARRAY_SIZE(action));
60 static int guc_log_control(struct intel_guc *guc, u32 control_val)
63 INTEL_GUC_ACTION_UK_LOG_ENABLE_LOGGING,
67 return intel_guc_send(guc, action, ARRAY_SIZE(action));
71 * Sub buffer switch callback. Called whenever relay has to switch to a new
72 * sub buffer, relay stays on the same sub buffer if 0 is returned.
74 static int subbuf_start_callback(struct rchan_buf *buf,
79 /* Use no-overwrite mode by default, where relay will stop accepting
80 * new data if there are no empty sub buffers left.
81 * There is no strict synchronization enforced by relay between Consumer
82 * and Producer. In overwrite mode, there is a possibility of getting
83 * inconsistent/garbled data, the producer could be writing on to the
84 * same sub buffer from which Consumer is reading. This can't be avoided
85 * unless Consumer is fast enough and can always run in tandem with
88 if (relay_buf_full(buf))
95 * file_create() callback. Creates relay file in debugfs.
97 static struct dentry *create_buf_file_callback(const char *filename,
98 struct dentry *parent,
100 struct rchan_buf *buf,
103 struct dentry *buf_file;
105 /* This to enable the use of a single buffer for the relay channel and
106 * correspondingly have a single file exposed to User, through which
107 * it can collect the logs in order without any post-processing.
108 * Need to set 'is_global' even if parent is NULL for early logging.
115 /* Not using the channel filename passed as an argument, since for each
116 * channel relay appends the corresponding CPU number to the filename
117 * passed in relay_open(). This should be fine as relay just needs a
118 * dentry of the file associated with the channel buffer and that file's
119 * name need not be same as the filename passed as an argument.
121 buf_file = debugfs_create_file("guc_log", mode,
122 parent, buf, &relay_file_operations);
127 * file_remove() default callback. Removes relay file in debugfs.
129 static int remove_buf_file_callback(struct dentry *dentry)
131 debugfs_remove(dentry);
135 /* relay channel callbacks */
136 static struct rchan_callbacks relay_callbacks = {
137 .subbuf_start = subbuf_start_callback,
138 .create_buf_file = create_buf_file_callback,
139 .remove_buf_file = remove_buf_file_callback,
142 static int guc_log_relay_file_create(struct intel_guc *guc)
144 struct drm_i915_private *dev_priv = guc_to_i915(guc);
145 struct dentry *log_dir;
148 if (i915.guc_log_level < 0)
151 /* For now create the log file in /sys/kernel/debug/dri/0 dir */
152 log_dir = dev_priv->drm.primary->debugfs_root;
154 /* If /sys/kernel/debug/dri/0 location do not exist, then debugfs is
155 * not mounted and so can't create the relay file.
156 * The relay API seems to fit well with debugfs only, for availing relay
157 * there are 3 requirements which can be met for debugfs file only in a
158 * straightforward/clean manner :-
159 * i) Need the associated dentry pointer of the file, while opening the
161 * ii) Should be able to use 'relay_file_operations' fops for the file.
162 * iii) Set the 'i_private' field of file's inode to the pointer of
163 * relay channel buffer.
166 DRM_ERROR("Debugfs dir not available yet for GuC log file\n");
170 ret = relay_late_setup_files(guc->log.runtime.relay_chan, "guc_log", log_dir);
171 if (ret < 0 && ret != -EEXIST) {
172 DRM_ERROR("Couldn't associate relay chan with file %d\n", ret);
179 static void guc_move_to_next_buf(struct intel_guc *guc)
181 /* Make sure the updates made in the sub buffer are visible when
182 * Consumer sees the following update to offset inside the sub buffer.
186 /* All data has been written, so now move the offset of sub buffer. */
187 relay_reserve(guc->log.runtime.relay_chan, guc->log.vma->obj->base.size);
189 /* Switch to the next sub buffer */
190 relay_flush(guc->log.runtime.relay_chan);
193 static void *guc_get_write_buffer(struct intel_guc *guc)
195 if (!guc->log.runtime.relay_chan)
198 /* Just get the base address of a new sub buffer and copy data into it
199 * ourselves. NULL will be returned in no-overwrite mode, if all sub
200 * buffers are full. Could have used the relay_write() to indirectly
201 * copy the data, but that would have been bit convoluted, as we need to
202 * write to only certain locations inside a sub buffer which cannot be
203 * done without using relay_reserve() along with relay_write(). So its
204 * better to use relay_reserve() alone.
206 return relay_reserve(guc->log.runtime.relay_chan, 0);
209 static bool guc_check_log_buf_overflow(struct intel_guc *guc,
210 enum guc_log_buffer_type type,
211 unsigned int full_cnt)
213 unsigned int prev_full_cnt = guc->log.prev_overflow_count[type];
214 bool overflow = false;
216 if (full_cnt != prev_full_cnt) {
219 guc->log.prev_overflow_count[type] = full_cnt;
220 guc->log.total_overflow_count[type] += full_cnt - prev_full_cnt;
222 if (full_cnt < prev_full_cnt) {
223 /* buffer_full_cnt is a 4 bit counter */
224 guc->log.total_overflow_count[type] += 16;
226 DRM_ERROR_RATELIMITED("GuC log buffer overflow\n");
232 static unsigned int guc_get_log_buffer_size(enum guc_log_buffer_type type)
235 case GUC_ISR_LOG_BUFFER:
236 return (GUC_LOG_ISR_PAGES + 1) * PAGE_SIZE;
237 case GUC_DPC_LOG_BUFFER:
238 return (GUC_LOG_DPC_PAGES + 1) * PAGE_SIZE;
239 case GUC_CRASH_DUMP_LOG_BUFFER:
240 return (GUC_LOG_CRASH_PAGES + 1) * PAGE_SIZE;
248 static void guc_read_update_log_buffer(struct intel_guc *guc)
250 unsigned int buffer_size, read_offset, write_offset, bytes_to_copy, full_cnt;
251 struct guc_log_buffer_state *log_buf_state, *log_buf_snapshot_state;
252 struct guc_log_buffer_state log_buf_state_local;
253 enum guc_log_buffer_type type;
254 void *src_data, *dst_data;
257 if (WARN_ON(!guc->log.runtime.buf_addr))
260 /* Get the pointer to shared GuC log buffer */
261 log_buf_state = src_data = guc->log.runtime.buf_addr;
263 /* Get the pointer to local buffer to store the logs */
264 log_buf_snapshot_state = dst_data = guc_get_write_buffer(guc);
266 /* Actual logs are present from the 2nd page */
267 src_data += PAGE_SIZE;
268 dst_data += PAGE_SIZE;
270 for (type = GUC_ISR_LOG_BUFFER; type < GUC_MAX_LOG_BUFFER; type++) {
271 /* Make a copy of the state structure, inside GuC log buffer
272 * (which is uncached mapped), on the stack to avoid reading
273 * from it multiple times.
275 memcpy(&log_buf_state_local, log_buf_state,
276 sizeof(struct guc_log_buffer_state));
277 buffer_size = guc_get_log_buffer_size(type);
278 read_offset = log_buf_state_local.read_ptr;
279 write_offset = log_buf_state_local.sampled_write_ptr;
280 full_cnt = log_buf_state_local.buffer_full_cnt;
282 /* Bookkeeping stuff */
283 guc->log.flush_count[type] += log_buf_state_local.flush_to_file;
284 new_overflow = guc_check_log_buf_overflow(guc, type, full_cnt);
286 /* Update the state of shared log buffer */
287 log_buf_state->read_ptr = write_offset;
288 log_buf_state->flush_to_file = 0;
291 if (unlikely(!log_buf_snapshot_state))
294 /* First copy the state structure in snapshot buffer */
295 memcpy(log_buf_snapshot_state, &log_buf_state_local,
296 sizeof(struct guc_log_buffer_state));
298 /* The write pointer could have been updated by GuC firmware,
299 * after sending the flush interrupt to Host, for consistency
300 * set write pointer value to same value of sampled_write_ptr
301 * in the snapshot buffer.
303 log_buf_snapshot_state->write_ptr = write_offset;
304 log_buf_snapshot_state++;
306 /* Now copy the actual logs. */
307 if (unlikely(new_overflow)) {
308 /* copy the whole buffer in case of overflow */
310 write_offset = buffer_size;
311 } else if (unlikely((read_offset > buffer_size) ||
312 (write_offset > buffer_size))) {
313 DRM_ERROR("invalid log buffer state\n");
314 /* copy whole buffer as offsets are unreliable */
316 write_offset = buffer_size;
319 /* Just copy the newly written data */
320 if (read_offset > write_offset) {
321 i915_memcpy_from_wc(dst_data, src_data, write_offset);
322 bytes_to_copy = buffer_size - read_offset;
324 bytes_to_copy = write_offset - read_offset;
326 i915_memcpy_from_wc(dst_data + read_offset,
327 src_data + read_offset, bytes_to_copy);
329 src_data += buffer_size;
330 dst_data += buffer_size;
333 if (log_buf_snapshot_state)
334 guc_move_to_next_buf(guc);
336 /* Used rate limited to avoid deluge of messages, logs might be
337 * getting consumed by User at a slow rate.
339 DRM_ERROR_RATELIMITED("no sub-buffer to capture logs\n");
340 guc->log.capture_miss_count++;
344 static void capture_logs_work(struct work_struct *work)
346 struct intel_guc *guc =
347 container_of(work, struct intel_guc, log.runtime.flush_work);
349 guc_log_capture_logs(guc);
352 static bool guc_log_has_runtime(struct intel_guc *guc)
354 return guc->log.runtime.buf_addr != NULL;
357 static int guc_log_runtime_create(struct intel_guc *guc)
359 struct drm_i915_private *dev_priv = guc_to_i915(guc);
361 struct rchan *guc_log_relay_chan;
362 size_t n_subbufs, subbuf_size;
365 lockdep_assert_held(&dev_priv->drm.struct_mutex);
367 GEM_BUG_ON(guc_log_has_runtime(guc));
369 /* Create a WC (Uncached for read) vmalloc mapping of log
370 * buffer pages, so that we can directly get the data
371 * (up-to-date) from memory.
373 vaddr = i915_gem_object_pin_map(guc->log.vma->obj, I915_MAP_WC);
375 DRM_ERROR("Couldn't map log buffer pages %d\n", ret);
376 return PTR_ERR(vaddr);
379 guc->log.runtime.buf_addr = vaddr;
381 /* Keep the size of sub buffers same as shared log buffer */
382 subbuf_size = guc->log.vma->obj->base.size;
384 /* Store up to 8 snapshots, which is large enough to buffer sufficient
385 * boot time logs and provides enough leeway to User, in terms of
386 * latency, for consuming the logs from relay. Also doesn't take
387 * up too much memory.
391 /* Create a relay channel, so that we have buffers for storing
392 * the GuC firmware logs, the channel will be linked with a file
393 * later on when debugfs is registered.
395 guc_log_relay_chan = relay_open(NULL, NULL, subbuf_size,
396 n_subbufs, &relay_callbacks, dev_priv);
397 if (!guc_log_relay_chan) {
398 DRM_ERROR("Couldn't create relay chan for GuC logging\n");
404 GEM_BUG_ON(guc_log_relay_chan->subbuf_size < subbuf_size);
405 guc->log.runtime.relay_chan = guc_log_relay_chan;
407 INIT_WORK(&guc->log.runtime.flush_work, capture_logs_work);
410 * GuC log buffer flush work item has to do register access to
411 * send the ack to GuC and this work item, if not synced before
412 * suspend, can potentially get executed after the GFX device is
414 * By marking the WQ as freezable, we don't have to bother about
415 * flushing of this work item from the suspend hooks, the pending
416 * work item if any will be either executed before the suspend
417 * or scheduled later on resume. This way the handling of work
418 * item can be kept same between system suspend & rpm suspend.
420 guc->log.runtime.flush_wq = alloc_ordered_workqueue("i915-guc_log",
421 WQ_HIGHPRI | WQ_FREEZABLE);
422 if (!guc->log.runtime.flush_wq) {
423 DRM_ERROR("Couldn't allocate the wq for GuC logging\n");
431 relay_close(guc->log.runtime.relay_chan);
433 i915_gem_object_unpin_map(guc->log.vma->obj);
434 guc->log.runtime.buf_addr = NULL;
438 static void guc_log_runtime_destroy(struct intel_guc *guc)
441 * It's possible that the runtime stuff was never allocated because
442 * guc_log_level was < 0 at the time
444 if (!guc_log_has_runtime(guc))
447 destroy_workqueue(guc->log.runtime.flush_wq);
448 relay_close(guc->log.runtime.relay_chan);
449 i915_gem_object_unpin_map(guc->log.vma->obj);
450 guc->log.runtime.buf_addr = NULL;
453 static int guc_log_late_setup(struct intel_guc *guc)
455 struct drm_i915_private *dev_priv = guc_to_i915(guc);
458 lockdep_assert_held(&dev_priv->drm.struct_mutex);
460 if (!guc_log_has_runtime(guc)) {
461 /* If log_level was set as -1 at boot time, then setup needed to
462 * handle log buffer flush interrupts would not have been done yet,
465 ret = guc_log_runtime_create(guc);
470 ret = guc_log_relay_file_create(guc);
477 guc_log_runtime_destroy(guc);
479 /* logging will remain off */
480 i915.guc_log_level = -1;
484 static void guc_log_capture_logs(struct intel_guc *guc)
486 struct drm_i915_private *dev_priv = guc_to_i915(guc);
488 guc_read_update_log_buffer(guc);
490 /* Generally device is expected to be active only at this
491 * time, so get/put should be really quick.
493 intel_runtime_pm_get(dev_priv);
494 guc_log_flush_complete(guc);
495 intel_runtime_pm_put(dev_priv);
498 static void guc_flush_logs(struct intel_guc *guc)
500 struct drm_i915_private *dev_priv = guc_to_i915(guc);
502 if (!i915.enable_guc_submission || (i915.guc_log_level < 0))
505 /* First disable the interrupts, will be renabled afterwards */
506 gen9_disable_guc_interrupts(dev_priv);
508 /* Before initiating the forceful flush, wait for any pending/ongoing
509 * flush to complete otherwise forceful flush may not actually happen.
511 flush_work(&guc->log.runtime.flush_work);
513 /* Ask GuC to update the log buffer state */
516 /* GuC would have updated log buffer by now, so capture it */
517 guc_log_capture_logs(guc);
521 int intel_guc_log_create(struct intel_guc *guc)
523 struct i915_vma *vma;
524 unsigned long offset;
525 uint32_t size, flags;
528 GEM_BUG_ON(guc->log.vma);
530 if (i915.guc_log_level > GUC_LOG_VERBOSITY_MAX)
531 i915.guc_log_level = GUC_LOG_VERBOSITY_MAX;
533 /* The first page is to save log buffer state. Allocate one
534 * extra page for others in case for overlap */
535 size = (1 + GUC_LOG_DPC_PAGES + 1 +
536 GUC_LOG_ISR_PAGES + 1 +
537 GUC_LOG_CRASH_PAGES + 1) << PAGE_SHIFT;
539 /* We require SSE 4.1 for fast reads from the GuC log buffer and
540 * it should be present on the chipsets supporting GuC based
543 if (WARN_ON(!i915_has_memcpy_from_wc())) {
548 vma = intel_guc_allocate_vma(guc, size);
557 if (i915.guc_log_level >= 0) {
558 ret = guc_log_runtime_create(guc);
564 /* each allocated unit is a page */
565 flags = GUC_LOG_VALID | GUC_LOG_NOTIFY_ON_HALF_FULL |
566 (GUC_LOG_DPC_PAGES << GUC_LOG_DPC_SHIFT) |
567 (GUC_LOG_ISR_PAGES << GUC_LOG_ISR_SHIFT) |
568 (GUC_LOG_CRASH_PAGES << GUC_LOG_CRASH_SHIFT);
570 offset = guc_ggtt_offset(vma) >> PAGE_SHIFT; /* in pages */
571 guc->log.flags = (offset << GUC_LOG_BUF_ADDR_SHIFT) | flags;
577 i915_vma_unpin_and_release(&guc->log.vma);
580 /* logging will be off */
581 i915.guc_log_level = -1;
585 void intel_guc_log_destroy(struct intel_guc *guc)
588 guc_log_runtime_destroy(guc);
590 i915_vma_unpin_and_release(&guc->log.vma);
594 int i915_guc_log_control(struct drm_i915_private *dev_priv, u64 control_val)
596 struct intel_guc *guc = &dev_priv->guc;
598 union guc_log_control log_param;
601 log_param.value = control_val;
603 if (log_param.verbosity < GUC_LOG_VERBOSITY_MIN ||
604 log_param.verbosity > GUC_LOG_VERBOSITY_MAX)
607 /* This combination doesn't make sense & won't have any effect */
608 if (!log_param.logging_enabled && (i915.guc_log_level < 0))
611 ret = guc_log_control(guc, log_param.value);
613 DRM_DEBUG_DRIVER("guc_logging_control action failed %d\n", ret);
617 if (log_param.logging_enabled) {
618 i915.guc_log_level = log_param.verbosity;
620 /* If log_level was set as -1 at boot time, then the relay channel file
621 * wouldn't have been created by now and interrupts also would not have
622 * been enabled. Try again now, just in case.
624 ret = guc_log_late_setup(guc);
626 DRM_DEBUG_DRIVER("GuC log late setup failed %d\n", ret);
630 /* GuC logging is currently the only user of Guc2Host interrupts */
631 gen9_enable_guc_interrupts(dev_priv);
633 /* Once logging is disabled, GuC won't generate logs & send an
634 * interrupt. But there could be some data in the log buffer
635 * which is yet to be captured. So request GuC to update the log
636 * buffer state and then collect the left over logs.
640 /* As logging is disabled, update log level to reflect that */
641 i915.guc_log_level = -1;
648 void i915_guc_log_register(struct drm_i915_private *dev_priv)
650 if (!i915.enable_guc_submission || i915.guc_log_level < 0)
653 mutex_lock(&dev_priv->drm.struct_mutex);
655 guc_log_late_setup(&dev_priv->guc);
657 mutex_unlock(&dev_priv->drm.struct_mutex);
660 void i915_guc_log_unregister(struct drm_i915_private *dev_priv)
662 if (!i915.enable_guc_submission)
665 mutex_lock(&dev_priv->drm.struct_mutex);
666 /* GuC logging is currently the only user of Guc2Host interrupts */
667 gen9_disable_guc_interrupts(dev_priv);
669 guc_log_runtime_destroy(&dev_priv->guc);
671 mutex_unlock(&dev_priv->drm.struct_mutex);